The present invention relates to a production scheduling method of and a production scheduling apparatus for planning a production program of products.
The following will discuss a production scheduling method of prior art. It is now supposed that the number of different products is defined as A, the name of each product is defined as i and the number of processes to be executed for producing each product i is defined as N(i) (which varies with the type of each product i). According to a production scheduling method of prior art, there is prepared a production program in which after the jth process of each product i, i.e., each process P(i,j) (i=1, . . . , A, j=1, . . . . , N(i)-1) has been finished, each subsequent process P(i, j+1) of each product i is executed.
The production program prepared by the production scheduling method of prior art, is arranged to instruct to execute invariably each subsequent process P(i, j+1) after completion of each process P(i,j). Accordingly, even though a defect has been found on a product i as a result of the inspection conducted after completion of the process P(i,j), the subsequent process P(i, j+1) is executed on the product i. This disadvantageously lowers the production yield, thus increasing the production cost.
According to the production scheduling method of prior art, the production cost of each product, the delivery delay term of each product, each system standby term and the like are not taken into consideration. This disadvantageously produces an increase in production cost, a delay in delivery term and an increase in system standby term.